html {
  -webkit-text-size-adjust: none;
  box-sizing: border-box;

  /* 兼容不支持vw浏览器的默认值 */
  font-size: 50px;
  /* (base/uiWidth)*100vw = (100/750)*100vw，之后使用rem单位时：设计稿100px-1rem，32px-0.32rem。这里设计稿总宽度为750px */
  font-size: 13.33vw;
}
@media (max-width: 320px) {
  html {
    font-size: 42px;
  }
}
@media (min-width: 640px) {
  html {
    font-size: 85px;
  }
}
*,
*:before,
*:after {
  box-sizing: inherit;
}
body {
  font-family: -apple-system,BlinkMacSystemFont,'Helvetica Neue',Helvetica,Segoe UI,Arial,Roboto,'PingFang SC','Hiragino Sans GB','Microsoft Yahei',sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  color: #2c3e50;
  font-size: 14px;
  background-color: #fff;
  max-width: 640px;
  margin: 0 auto!important;
}
body, p, h1, h2, h3, h4, h5, h6, ul, li {
  margin: 0;
  padding: 0;
}
a {
  color: #1890ff;
  text-decoration: none;
}
ul{
  list-style: none;
}